Equivariant biharmonic maps between manifolds with metrics of signature

Abstract

We obtain the reduction theorem of equivariant biharmonic maps between warped product manifolds, and apply it to punctured Euclidean spaces, spheres and hyperboloids. We also investigate equivariant biharmonic maps from equivariant manifolds with metrics $$(p, \, q)$$ -signature into equivariant manifolds with $$(p', \, q')$$ -signature, prove the reduction theorem, and provide a few examples.